J. Biol. Chem. Chron. 2020, 6(1), 01-04 ISSN (Print): 2454 – 7468 ISSN (Online): 2454 – 7476 www.eresearchco.com/jbcc/ An Account of Epiphytic Orchids of Nainital in Relation to Their Host Specificity Jyoti1* and L. M. Tewari2 1 & 2 Department of Botany, D. S. B. Campus, Kumaun University, Nainital- 263 001, Uttarakhand, INDIA * Correspondence: E-mail: [email protected] DOI: http://dx.doi.org/10.33980/jbcc.2020.v06i01.001 (Received 20 Dec, 2019; Accepted 27 Jan, 2020; Published 29 Jan, 2020) ABSTRACT: Orchids are highly evolved and specialized group of flowering plants belonging to family Orchidaceae. It is the second largest family of the flowering plants in the world with more than 24,000 species of perennials that includes terrestrial, saprophytic, lithophytic and epiphytic species. The present work is based on the systematic ephiphytic orchids observations based on habit, habitat, colour of flower, flowering period and detailed morphologi- cal features. Twenty-two epiphytic orchid species belonging to fifteen genera were recorded from Nainital area. The genera represented were Dendrobium (four species), Aerides, Bulbophyllum, Eria and Oberonia (two species each) while rests were represented by single species each. The host species such as Quercus leucotrichophora (6), Sapium insigne (5), Syzygium operculatum, Bombax ceiba and Pyrus pashia (4) supported maximum number of epiphytic orchids followed by the species Syzygium cumini and Toona ciliata (3). Four host species reported with single orchid species. Due to high anthropogenic pressure and changing environmental conditions resulted in vulnerability of these species. Therefore, regular monitoring of the species, mass scale propagation and creating awareness among the local inhabitants are suggested. Keywords: Orchidaceae; saprophytic; epiphytic; monitoring and propagation. INTRODUCTION: Orchids comprise unique assem- 1991). The distribution of the orchids within state, blage of highly advanced monocotyledonous plants. however, is extremely patchy, they are mainly con- Orchids are the most diverse group of flowering centrated along the riverine areas and pockets of moist plants; estimated number of species ranges from forests (Jalal, 2005). The changing environmental 17,000 to 35,000 (Dressler, 1981). About 73 percent conditions, land use patterns, over grazing, fodder of the orchid species are epiphytes (Atwood, 1986), purposes, over-exploitation and expanding urbaniza- and contribute significantly to the epiphytic plant tion have resulted in shrinkage and degradation of communities in the tropical forests. The Indian Hima- natural habitats causing threat to floristic diversity, layan Region (IHR) supports about 8,000 flowering including orchids. In view of the importance of orc- plants and family Orchidaceae is one of the species hids in various ways the present study has been con- rich families of angiosperms (Samant, 2002; Singh ducted in and around of Nainital area of Uttarakhand and Hajra, 1996). In India, 9% of flora (1300 species with a view to: i) Identify and document the epiphytic and 140 genera) is composed of orchids and is present orchids; ii) Identify their host species and distribution; predominantly in temperate Himalaya (Yonzone et al., and iii) Suggest conservation & management options. 2010). These are terrestrial, epiphytic and saprophytic in nature and are cultivated for beautiful flowers and MATERIALS AND METHODS: widely known for their economic importance but less Study Area: Present study is carried out in Nainital for their medicinal value. The diversity of orchids and its surrounding areas. Nainital catchments lies decreases from North East to North West Himalaya between 29° 19′-29° 28′ N latitudes and 79° 22′-79° (Chowdhery and Agarwal, 2013; Deva and Naithani, 38′ E longitudes in the Kumaun Himalaya (Figure 1). 1986; Samant et al., 1995 Samant, 2002). Uttarakhand The entire area is hilly with an altitudinal range up to with about 237 species ranks fifth among the Indian 2200m asl. The study area experiences between sub- states in terms of orchid richness. State is blessed with tropical to temperate climate on high elevation. Rain- different and unique species of orchids (Pangtey et al., fall begins earlier in the month of June and continues J. Biol. Chem. Chron. 2020, 6(1), 01-04 1 [An Account of Epiphytic Orchids of Nainital in Relation to Their Host Specificity] up to the end of September. Nainital records heavy Luisia, Ornithochilus, Pholidota, Rhynchostylis, rainfall in these months mainly because of the local Smithandia, Thunia and Vanda one species each (Fig- rain. Predominantly occurred plant species composed ure 2). The host species such as Quercus leuco- of temperate genera, such as - Quercus leucotrico- trichophora (6), Sapium insigne (5), Syzygium opercu- phora, Quercus semicarpifolia, Rhododendron ar- latum, Bombax ceiba and Pyrus pashia (4) supported boreum, Acer oblongum, Cedrus deodara Roxb., but maximum number of epiphytic orchids followed by in catchments of lower lakes at 1200-1400m altitudes the species Syzygium cumini and Toona ciliata (3). tropical and subtropical plants such as species of Bau- However four host species reported with single orchid hinia variegate, Butea Roxb. and Pinus roxburghii species. Species such as Aerides multiflora, Aerides Roxb. Forests are also reported. These species are also odorata, Rhynchostylis retusa, Dendrobium amoe- seen running down as low as 1100 m in elevation in num, Pholidata articulate and Smitihandia micrantha moist ravines and form more or less distinct altitudinal have wide range of host species (Figure 3). However zones. two species Oberonia ensiformis and Oberonia pachyrachis reported only in single host. Pinus rox- burghii was also reported as host may be due to high humidity in this region. The species with maximum number of hosts are widely distributed and hence are less vulnerable to change in environment where as the species that have single hosts are the most vulnerable and locally rare orchid species in the study area. The major threats are destruction of riverine habitats, ex- traction of fodder and fuel from the host plant, attack of wild animals, misuse of the beautiful orchids just for ornamental purpose etc. Figure 1: Map of the study area. Table 1: List of epiphytic orchid species. Surveys, Samplings, Identification and Data Anal- S.No. Species Habit ysis: Extensive field survey was conducted during 1 Aerides multiflora Roxb. E&L 2014 in Nainital and surrounding areas. Rapid sam- 2 Aerides odorata Lour. E&L pling was done along the topographical gradients i.e., 3 Bulbophyllum cariniflorum Rchb. f. E altitude, habitat and aspect for the survey of orchids. 4 Bulbophyllum polyrhizum Lindl. E For epiphytic orchids in each locality, altitude, host species and their bark types were recorded. In each 5 Coelogyne cristata Lindl. E&L host species the numbers of epiphytic orchid species 6 Dendrobium amoenum Wall.ex Lindl. E&L were counted. Host species were identified using 7 Dendrobium bicameratum Lindl. E standard flora and by comparing with herbarium spe- 8 Dendrobium crepidatum Lindl. E cimens. For identification of orchid species, several 9 Dendrobium primulinum Lindl. E referral works including (Anonymous, 1883; Deva 10 Eria lasiopetala (Willd.) Ormerod E&L and H. B. Naithani, 1986; Duthie, 1906; Jalal 2005; 11 Eria spicata (D.Don) Hand.-Mazz. E&L King and Pantling, 1898; Kumar and Manilal, 1994; Gasrtochilus calceolaris (Buch.-Ham. ex 12 E Misra 2007; Pangtey and Samant, 1991; Pangtey et Sm.) D.Don al., 1991; Polunin and Stainton, 1984; Vij et al., 1983; 13 Kingidium taeniale (Lindl.) Hunt E were used. Threat categories of the species have been 14 Luisia tristis (G.Forst.) Hook.f. E&L identified based on habitat preference, population size, 15 Oberonia ensiformis (J. E. Sm.) Lindl. E distribution range and use values (Rana and Samant, 16 Oberonia pachyrachis Rchb.f. ex Hook.f. E&L 2010). Ornithochilus difformis (Wall.ex Lindl.) 17 E Schltr. RESULTS AND DISCUSSION: Twenty-two epi- 18 Pholidata articulata Lindl. E&L phytic orchid species belonging to fifteen genera were recorded from Nainital area (Table 1). This diversity 19 Rhynchostylis retusa (Lindl.) Blume E&L represents 40% of the orchids reported from Nainital 20 Smitihandia micrantha (Lindl.) Holtt. E area. The genera represented were Dendrobium (four 21 Thunia alba (Lindl.) Reichb. E&L species), Aerides, Bulbophyllum, Eria and Oberonia 22 Vanda cristata Lindl. E (two species), Coelogyne, Gasrtochilus, Kingidium, J. Biol. Chem. Chron. 2020, 6(1), 01-04 2 [An Account of Epiphytic Orchids of Nainital in Relation to Their Host Specificity] tourism related activities are main reasons which leads toward the phase of extinction of these unique species. Orchids are very sensitive to ecological changes. Proper and repetitive monitoring of study sites is re- quired to suggest suitable management plans. Partici- pation of local inhabitants is must to raise awareness among them about their conservation. Mass scale propagation of the orchids by in-situ and ex- situ con- servation strategies is need of the hour. Dendrobium amoenum Figure 2: Host species of epiphytic orchids. Aerides multiflora Vanda cristata CONCLUSION: The present study highlights the Figure 3: Epiphytic orchid species in relation to diversity and distribution of epiphytic orchids with host species. correlation to their host species. High humidity and Himalayas are blessed with unique range of floristic temperature favour the growth of diverse